Thread guide for stop motions



July 28, 1931. A. CRAWFORD 1,816,765

THREAD GUIDE FOR STOP MOTIONS Filed Dec. 10. 1929 ent'to Frank Crawford Patented July 28, 1931 UNITED STATES PATENT OFFICE ALFRED CRAWFORD, OF NEW BRUNSWICK, NEW JERSEY, ASSIGNOR T0 CRAWFORD MANUFACTURING COMPANY, 01? NEW BRUNsWioK, New

OF NEW JERSEY JERSEY, A CORPORATION THREAD GUIDE FOR STOP lflOTlIONS Application filed December 10, 1929. Serial NO. 413,034.

This invention relates to thread guides of the type shown and described in a prior pat- No. 1,558,932, dated September 15, 1925.

I I 5 Thread guides'of this type are employed with stop motions for knitting machines employing one or more threads, some of which at times remain idle While others carry on the knitting operation, such, for example, as in hosiery knitting machines employing one or more body threads'and one or more reinforcing or plating threads, any of which may at times remain idle while others are knitting, and it has been found that, after any thread has stopped knitting and remains idle, or after the entire knitting machine has been stopped by means other than the tripping of the stop motion and permitted to stand for a prolonged period of time, the idle thread or threads which are being held in the respective thread guides become slack, due to factory vibrations, etc.,'which at times permits a thread to work out from between the movable trip plate' and the stationary plate of the thread guide, thereby permitting the trip plate to drop, which trips the stop motion.

The present invention relates to means for preventing such accidental displacement of thread relative to the co-operating trip plate andthestationary plate of the thread guide through which the thread passes, whereby such false tripping of the, stop motion is obviated.

In the accompanying drawings:

Fig. 1 is a side elevation of a thread guide embodyingthe improved featureforming the subject of the present invention;

' Fig. 2-is a plan view; I [Fig 3 is a sectional plan view line 3-8, of Fig. 1, showing the thread in a taut. condition Fig. 4 is a similar sectional plan view, but showing the relation of the elements when the thread is in a slack condition;

Fig. 5' is a perspective View of the stationary plate of the thread guide; and

Fig. 6 is a perspective View of the movable trip plate. eferring to Fig. 1 of the drawings, 1 is a bracket projecting from the body portion taken on the of a stop motion (not shown). Secured to the bracket 1 is a thread guide 2, which as shown in Figs. 3, 4 and 5 consists'of a flat plate bent into a U-shape as indicated at 3 to form a front plate 4 and a rear plate 5. The free ends of the plates 4 and 5 are respectively flared as indicated at 6 and 7, to facilitate the insertion of a thread a between the said plates 4' and 5. I

The front plate 4. has a series of parallel slots 10 formed therein, which are separated by ribs or bars 11, 11. The ribs or bars 11 are bent to form or otherwise provided with shoulders 12.

The rear plate 5 is provided with slots 13, 13 which are located directly behind the slots 10 in the front plate 4.

Mounted in a bearing 14 on the bracket 1 is one end of a shaft 15 on the outer end of which is secured a trip arm 16. Secured to I )late 4. The outer ends of the iin crs 18are bent inwardly at an acute angle with respect to the plane of the fingers as indicated at 19, forming a. resilient thread-retaining element on the finger or what may be conveniently termed a spring barb, which will yield. to permit the passage of a thread laterally between the front plate 4"and the said barb, but which will spring.outwardly after the thread has passed beyond the free endof the barb and behind the shoulders 12 of the ribs or bars 11 ofthe front plate 4.

- Fig. 3 shows in broken lines the yielding of the spring barb 19 to permit the thread a to pass and, also, in full lines, the position assumed by the trip plate 17 when the thread is drawn taut by the operation of the machine," the rear plate '5 limiting the backward movement of the trip plate 17.

Fig. 4 illustrates the position of the trip plate 17 when the thread a has becomeslack outwardly between the bars 11 into the slots 10, confining the thread a behind the shoul ders 12. However, if vibrations should cause luv the trip plate to be oscillated between the positions shown in Figs. 3 and 4 respectively. the thread in any event would be caught behind the spring barb 19 of the trip plate 17, should the thread have a tendency to move outwardly from between the plates 4 and 5, for the reason that the free end of the spring barb occupies a position within the slot 10 beyond the inner face of the front plate 4- At the top 01 the thread guide is a plate 20 notched at 21 to receive the thread a and at the bottom of the thread guide is an eye :22 through which thethread a also passes. The opening 13 in the rear plate 5 permits of abackward fiexure of therfingers 18 in addition to the fieriureof the barbs 19in inserting a thread in the thread guide, however, these openings may be omitted if desired, in the'present form of the invention.

I claim:

I. In a thread guide for stop motions, the combination of a stationary element, a trip element movable laterally with respect to said stationary element, meansfor limiting the trip element in one direction relative to said stationary element to provide a thread receiving space therebetween, and a spring barb carried by the trip element and extending across the said thread receiving space and adapted for relative movement with respect to and independent of said trip element to provide for the passage of a thread into said thread-receiving space.

2. In a thread guide for step motions, the combination or" a stationary element, a trip element movable laterally with respect to said stationary element, means for limiting the trip element in one direction relative vto said stationary element to provide a thread receiving space therebetween, and a spring barb formed integral with and extending laterally froniand at an acute angle/with respect to the trip element and across the said thread receiving space to a point beyond the adjacent wall of the said stationary element and adaptedto be flexed toward said trip element to provide for the passage of a thread into said thread-receiving space.

3. In a thread guide for stop motions, the combination of a stationary thread guide comprising a plate bent into a U-shaped form providing a pair of parallel walls one of which is provided with a slot extending outwardly from the bend in the plate, a trip element comprising a finger movable laterally of the stationary guide through the slot formed in the one wall thereof, to form a thread receiving space between the finger and the said slotted wall, and a spring barb on the finger and extending across the said thread receiving space from the said finger to the said slotted wall and adapted to be flexed to- I ward said trip element to provide for the passage of a thread into said thread-receiving space.

4. In a thread guide for step motions, the combination of a stationary thread guide comprising a plate bent into a U-shaped form providing a pair of parallel walls one of which is provided with a slot extending outwardly from the bend in the plate, a trip element comprising a finger movable laterally of the stationary guide through the slot formed in the one wall thereof, to form a thread receiving space between the finger and the said slotted wall, a spring barb on the finger and extending across the said thread'receiving space from the said finger into the slot in said wall and adapted to be flexed toward the finger to provide for the passage of a thread into said threadereceiving space, and a shoulder on the said slotted wall adjacent-the free end of the said barb and extending into the said thread receiving space.

5. In a thread guide for step motions, the' combination of a stationary thread guide comprising a plate bent into 'a U-shaped form providing a pairof parallel walls one of which is provided with a slot extending outwardly from the bend in the plate, a trip element comprising a finger movablfelaterally of the stationary guidethrough the slot formed in the one wall thereof, to form a thread receiving space: between the finger and the said slotted wall, the outer end of said finger being bent back over the finger and atan acute angle with respect thereto to form a spring barb on the finger adapted to extend across the said thread receiving space to the adjacent wall of the stationary thread guide and to be flexed toward the finger to provide for the passage of the thread-into the threadreceiving space.

6. In athre'ad guide for step motionsthe combination of a stationary thread guide comprising a plate bent'into a U-shaped form providing a pair of parallel walls one of whichis provided with a slot extending outwardly from the bend in the plate, a trip 7 element comprising a finger movable lateral-- ly of the stationary guide through the slot formed in the onewall thereof, to form a thread receiving space between thefinger and the said slotted wall. the outer end of said fin- 'ger being bent back over the finger and at an i acute angle with respect thereto to forms. spring barb onthe finger adapted to extend across the said thread receiving space to the adjacent wall of the stationary thread guide into the slot in said wall and to be flexed toward the finger to permit the passage of a thread into the said thread-receiving space,

and a shoulder on the said slottedwall adjaing into the said thread receiving space.

cent the free end of thesaid barb and extend- 7 

